US1945487A - Electric switch - Google Patents

Description

Jan. 30, 1934. F E JOHNSON 1,945,487

ELECTRIC SWITCH Filed July i5, 1929 Patented Jan. 30, 1934 PATENT FFCE ELECTRIC SWTCH Frank E. `lohnson, New Bedford, Mass., assigner to .lohn l. Paulding, line., New Bedford, Mass., a corporation of Massachusetts Application July 15, 1929. Serial No. 378,306

Claims. (Cl. 20th-67) This invention relates to an electric switch and 22 of the rocker member and the other leg 28 more particularly to a snap switch adapted to be for anchoring the terminal on the insulating operated by turning a button. body. The latter is provided with a pair of bores One of the important objects of the invention 30 in its rear face each of which is connected to is t -e provision of a switch of the character dethe front face by a 'i`-shaped opening or slot 32 scribed which is of such compact and simplified (Fig. 5) the head of each slot being adapted to construction that it can be made and assembled receive and hold the leg 28 of one of the terminals. at a very low cost. A hOle 84 is punched in the head of the terminal Another important object is the provision of a for receiving loosely a binding screw 36 which is o switch in which the actuating spring is operated held therein by a square nut in the bore 30 (Fig. i5

by a cam action effected by turning a button. 3) After each terminal has been mounted in Other objects of the invention will be more speplace (Fig. 7 and the binding screw turned down, cically pointed out and described hereinafter. the bore 30 in each case is lled with the insulat- In the accompanying drawing illustrating one ing wax which news around the square nut and y form of the invention, Figure l is a front elevaleg 28 and when hardened locks them in position. 30 tion of a switch constructed and adapted to be To insure further the locking of the leg 28, it operated in accordance with my invention; Fig. 2 may be cut out at the side points 40. After the is a front elevation of the same with the operating insulating wax has hardened the turning up of button and cover removed; Fig. 3 is a rear elevathe binding screw will not disturb the nut which tion; Fig. 4 is a central sectional view on line will be held in position between the wax and the iii- 4-4 in Fig. l; Fig. 5 is a front elevation oi the ininner end of the bore. sulating body showing one nxed contact mounted This form of terminal has a number of adtherein; Fig. 6 is a central sectional view on Vantages. It combines a ixed contact and terline 6-6 in Fig. l with the cover removed; Fig. minal in one piece which can be stamped out of 7 is a sectional view on line '7-7 in Fig. 5; Fig. 8 is sheet material and shaped in one operation. It Si a plan view of the cam slide; Fig. 9 is a plan View obviates tapping and threading two holes, which of the cam and Fig. l0 is a view in perspective of are generally required, one for the fastening screw a terminal contact. and the other for the binding screw, and which In the illustrated embodiment of the invention are expensive operations. It also facilitates the l2 designates an insulating body of any suitable assembling operation by eliminating the fastening tti form for holding the switch parts. As shown, of the terminals to the insulating body by the however, the body is circular in plan and is prouse of screws or equivalent devices. vided in its front face with a deep recess or cham- It will be observed that the bases of the grooves ber 14 within which is loosely mounted a rocker 2G are flat which permits of a slight movement member 16 of any suitable form, but preferably in a lateral direction of the rocker member in its U-shaped in plan and adapted to be stamped out bearings in order to insure a positive contact beof sheet material. The two ends 18 of the rocker tween the rocker member and the fixed contacts member are turned outwardly to form journal in case the latter are slightly out of alignment. portions to fit in V-shaped grooves 2O formed in .in such case the pressure of the actuating spring the side walls of the recess 14 which grooves act twists the rocker member in its bearings sui- 95 as bearings for said member. The end walls cf ciently to hold it against both fixed contacts. said recess serve as stops to limit the movement For actuating the rocker member to open or to of the rocker member. On the base portion of close the circuit a spring 42 is provided which is said member are formed two separated extension operated by a slide 44 reciprocated by a cam 46 45 or contact portions 22 which are turned up on mounted on a turn button 48. The slide 44 (Fig. 100

one side in angular relation to the main body of 8) is in the form of a rectangular plate having said member (Fig. Il) for engaging and bridging turned end nanges for engagement a pair of fixed separated contact terminals 24 iasby the cam (i6 whic is eccentrically mounted on tened to the rear face of the insulating body. the threaded stem 52 of the turn button 48.

50 The form of the contact ter". inals and the Stamped out of the body of the slide and turned 05 method of fastening them to the insulating body downwardly is a tongue 54 having an end hold constitute one important feature of the inven- 56 through which one end of the actuating helition. Each of the terminals 2li is substantially cal spring 42 is passed and locked, the other end U-shaped (Fig. le) one leg 26 serving as a conof which encloses loosely an upwardly projecting 55 tact to be engaged by one of the contact portions lug 58 on the base of the rocker member. Since 110 the spring is under compression at all times its lower end remains on the lug andrholds the rocker member downwardly in its bearings.

For holding and guiding the cam slide, a guide plate is fastened to projecting portions 62 of the front face of the body l2 which plate may be or" any suitable form but as shown simulates a cross (Fig. 2). It is secured to the body by two screws 64 mounted from the inner face of the body in suitable bores and threaded into the ends of two opposite arms of the plate. The other two opposite arms are provided each with a longitudinal open slot 66 into which projects a lug 63 formed on one of the end iianges of the cam slide and the slots and lugs act to guide the cam slide in its reciprocating movement.

Between the cam slide and guide plate is arranged the cam 46 preferably a circular disk in form, having a threaded hub 69 eccentrically located (Fig. 9) for receiving the threaded stem of the button e3. The guide plate is provided with a central hole for receiving the hub 69 of the cam and the latter is rotated eccentrically by the turn button in a clockwise direction. The cari slide is supported and slides on shoulders 70 formed in the `insulating body. On its periphery the cam may have a tooth 72 formed to facilitate the removal of the turn button from the cam by turning the button contra-cioclnvise. lr" the button sticks when thus turned and ten to carry the cam in the latter direction the tooth will engage one end of a flange 50 and lock the cam against further movement in that direction and the turn button can then be unscrewed from the cam.

For concealing the switch mechanism a cover 74 of any suitable form is provided having a central hole I5 for the insertion of the turn button in the cam ait-er the cover has been mounted in place. To remove the cover it is of course necessary to rst remove the turn button which frees the cover. The ange 76 of the cover is provided with an edge notch 77 to receive a projection 78 formed in the rim of the body l2 to prevent rotary movement of the cover. y Y

To indicate the position of the switch mechanisrn and whether the current is ofi or on, the cam slide on one side is provided with two upstanding lugs SG upon which is inserted a light plate 82 having marked thereon any suitable designations to indicate the two positions of the switch such as Ofi and On, and the cover has an opening 84 which exposes the proper designation to indicate the position of the switch. For

installing the switch the insulating body is pro- Turning the button in a clockwise direction turns the cam and moves the cam slide which carries the upper end of the actuating spring across the plane of the rocker member. As soon as the upper end oi the spring passes through plane, the spring throws the rocker member over and completes the movement oi the cam slide as far as it can go and holds the parts in that position until the button is again turned to reverse the action.

It will be observed that my invention greatly reduces the number of parts of the switch by utilizing the insulating body for bearings thereby eliminating separate bearing parts and fastening means therefor. The assembling and mounting of the switch mechanism in the insulating body is greatly simplied since it requires but the two screws for fastening the guide plate in place which holds all the parts in operative position.

It will be apparent that switches constructed in accordance with my invention can be produced and assembled with great rapidity and at a very low cost. Not only does the simplicity of construction contribute to compactness and cheapness but also to efficiency and durability.

,it is to be understood that the foregoing described embodiment of the invention is merely to illustrate the one application of the invention which may be embodied in various other forms all within the scope of the iollowing claims.

What I claim is:

l. An electric switch having, in combination, a recessed insulating body, a pair of xed contacts mounted in said recess in separated relation, a U-shaped rocker member pivotally mounted in nat-bottomed grooves in the side walls or said recess for bridging said contacts, said member having a pair of upwardly extending extensions for engaging latwise said fixed contacts, a spring for actuating said rocker member to open and close the circuit through said fixed contacts, a

cam-slide connected to one end of said spring and movable on shoulders formed on the insulating body, a cam for reciprocating said camslide to operate said spring, a guide plate fastened to said insulating body for controlling the;

movement of said cam-slide and for holding said cam in operative position and means for operating said cai 2. In an electric switch, the combination ci a recessed insulating body, a pair of xed contactsilf:

ing said rocker member, a slide connected to one-115 end of said spring, said slide having upturned end flanges, and a button .operated cam mounted between said end iianges for reciprocating said slide, to actuate said rocker member.

3. An electric switch having, in combination, afi12o recessed insulating body, a cam slide adapted for reciprocatory movement on shoulders formed in said body, a guide plate fastened to said insulating body for guiding said cam-slide, a cam intermediate said plate and said slide for reciproT-lzs eating said slide and a switch member connected to and adapted to be operated by said cam slide.

4. An electric switch having, in combination, a pair of fixed contacts, a U-shaped rocker member for bridging said contacts, said member hav-1.1130

ing upturned extensions for engagement atwise with said contacts, a spring :for actuating said rocker member, a cam slide provided with upturned end flanges and attached to one end ci said spring, guiding means for said cam slide, a 13E cam for reciprocating said cam slide by engagement with said end flanges to operate said spring and a button eccentrically mounted in said cam for operating the same.

5. in an electric switch, the combination of a lli-l a button for A5

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